Research On Energy And Mobility Aware Routing Protocol For Hybrid Wireless Mesh Networks

Hybrid Wireless Mesh Networks(WMN) have been considered to be an ideal wireless broadband Internet access solutions, because it has a stronger network connectivity, improved network reliability and larger coverage. Routing protocols provide the effective routing basis for communications among nodes of network, which directly affects the network throughput, packet loss rate and other properties. Thus, the research on hybrid WMN Routing protocols has importance for improving overall network performance.Existing researches of WMN routing protocols are focused on infrastructure mesh networks or client Mesh networks, hybrid WMN routing studies are relatively few reported. In hybrid WMN, the mesh client has the mobility and constrained energy, which will affect the stability of path and network lifetime. The multi- hop communication of clients will cause diversity of communication links, the existing infrastructure mesh routing protocols is no longer suitable for hybrid WMN. Therefore, designing a routing protocol based on comprehensively consideration of the network status and node characteristics of hybrid WMN has important theoretical significance a nd application value for the future development of broadband wireless communications.This paper proposes an energy and mobility aware(EMA) routing protocol, owing to the issue of existing hybrid WMN routing protocols failed to comprehensively consider the network interference, load, mobility and energy constraints of mesh clients. On the basis of AODV protocol, EMA routing protocol uses a new proposed energy and mobile aware(MEMA) routing metric as the routing criteria. MEMA metric uses method of cross- layer design to capture the channel utilization of MAC layer, path length of routing layer, nodes’ speed and residual energy of application layer as metric parameters, which can comprehensively consider the effects of network interference, load, mobility and energy-constrained characteristics of mesh clients on the network status, so as to select a high throughput and stable path. Meanwhile, in order to solve the problem that client’s forwarding feature brings a lot of flooding overhead, this paper designs a constrainted forwarding mechanism to optimization EMA routing protocol, effectively reducing the cost and save energy. NS2 simulation results show that the network performance of EMA routing protocol is significantly improved in terms of throughput, packet loss rate, average delay, network overhead and energy consumption client.On the basis of above researches, in order to solve the issue that existing hybrid WMN routing protocols do not consider the impact of Mesh clients’ energy constraints on the network lifetime, this paper proposes a regional energy and mobility aware(REMA) routing protocol, which makes the selected path is more stable. REMA protocol improves MEMA routing metric from two major aspects:(1) the degree of average concentration is used to be aware of energy consumption intensity and the degree of dispersion within the nodes’ communication transmission range, so as to select the area that has sufficient residual energy for network services, achieving energy balancing and extend the network lifetime;(2) the degree of average dispersion is used to re- measure the impact of the clients’ mobile speed on the network status, which enhance s the stability of the path and reduces the network overhead. REMA routing protocol is not only more accurate ly being aware of the impact of the clients’ energy constraints and mobility on the network status, but also balances network energy consumption and prolongs network lifetime. NS2 simulation results show that REMA routing protocol can significantly improve network performance, balance energy and network load, and achieve the purpose of prolonging network lifetime.The work and research achievements of this paper could provide references for the research on energy and mobility aware routing metric in wireless Mesh networks.